J O U R N A L O F T H E M E C H A N I C A L B E H AV I O R O F B I O M E D I C A L M AT E R I A L S
4 (2011) 1473–1482
available at www.sciencedirect.com
journal homepage: www.elsevier.com/locate/jmbbm
Research paper
Respective roles of organic and mineral components of
human cortical bone matrix in micromechanical behavior: An
instrumented indentation study
Y. Bala a,b,c,∗,1 , B. Depalle a,b,c,1 , T. Douillard d , S. Meille d , P. Clément d , H. Follet a,b,c ,
J. Chevalier d , G. Boivin a
a INSERM, UMR1033, F-69008, Lyon, France
b Université de Lyon, Lyon, France
c Hospices Civils de Lyon, France
d Université de Lyon, INSA-Lyon, MATEIS, CNRS UMR 5510, F-69621, Villeurbanne, France
A R T I C L E
I N F O
A B S T R A C T
Article history:
Bone is a multiscale composite material made of both a type I collagen matrix and a poorly
Received 8 March 2011
crystalline apatite mineral phase. Due to remodeling activity, cortical bone is made of
Received in revised form
Bone Structural Units (BSUs) called osteons. Since osteon represents a fundamental level
14 April 2011
of structural hierarchy, it is important to investigate the relationship between mechanical
Accepted 7 May 2011
behavior and tissue composition at this scale for a better understanding of the mechanisms
Published online 17 May 2011
of bone fragility. The aim of this study is to analyze the links between ultrastructural
properties and the mechanical behavior of bone tissue at the scale of osteon.
Keywords:
Iliac bone biopsies were taken from untreated postmenopausal osteoporotic women,
Human cortical bone
embedded, sectioned and microradiographed to assess the degree of mineralization of
Mineralization
bone (DMB). On each section, BSUs of known DMB were indented with relatively high load
Indentation
(∼500 mN) to determine local elastic modulus (E), contact hardness (Hc ) and true hardness
Hardness
(H) of several bone lamellae. Crystallinity and collagen maturity were measured by Fourier
Collagen maturity
Transform InfraRed Microspectroscopy (FTIRM) on the same BSUs. Inter-relationships
between mechanical properties and ultrastructural components were analyzed using
multiple regression analysis.
This study showed that elastic deformation was only explained by DMB whereas plastic
deformation was more correlated with collagen maturity. Contact hardness, reflecting both
elastic and plastic behaviors, was correlated with both DMB and collagen maturity. No
relationship was found between crystallinity and mechanical properties at the osteon
level.
c 2011 Elsevier Ltd. All rights reserved.
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∗ Corresponding address: INSERM UMR 1033 Equipe “Qualité Osseuse et Marqueurs Biologiques”, Université de Lyon, Faculté de Médecine
Lyon Est, Claude Bernard (Domaine Laennec), 7-11 rue Guillaume Paradin, 69372 Lyon Cedex 08, France. Tel.: +33 4 78 78 57 35; fax: +33 4
78 77 86 63.
E-mail addresses: [email protected], [email protected] (Y. Bala).
1 The first two authors contributed equally to this work.
c 2011 Elsevier Ltd. All rights reserved.
1751-6161/$ - see front matter ⃝
doi:10.1016/j.jmbbm.2011.05.017